[Pythoncad-developer] Pushed many changes to the R38 branch

[<ger...@gm...>]

Hello,

I just pushed many changed into the R38 repository.

This means the old drawing methods are mostly replaced by the new cairo  
ones.
All draw functions (entity draw and rubberbanding and future selection  
draw) are now in the <entity>draw.py modules.

Not all entity draw functions are replaced by new ones, I will convert them  
one by one the next days.
There are issues with drawings when a very large part of the entity is off  
screen (maybe need some clipping).
There are issues with rubberbanding which can be slow at some times (after  
dynamic zoom with mouse wheel while drawing).
Mouse wheel zoom is pointer position sensitive, zooming is done around the  
mouse pointer and not screen center.

At this stage the cairo drawing should give a good indication of the  
performance which can be achieved.
I have not done any optimizations but I don't think it will be more than  
1.5x faster as it is now.
At least the panning is faster now (but after pan a redraw it needed which  
can be slow for large drawings).
Also each dynamic zoom with the wheel mouse button requires a redraw.
When zoomed into a small part of the drawing less entities are drawn than  
redraw is faster, whole drawing redraw is still slow.

Please look at the drawing performance and share your feelings (is it fast  
enough, does it need changes).
I think for really good performance you need display lists as used in  
opengl.

Regards,
Gertwin